[C++] Implement boolean selection kernels

[asfimport]

Select values where a boolean selection array is true. As a default, if any values in the selection are null, then values in the output array should be null.

The null behaviour does not need to be toggable, if the user wants to select nothing in the case of null, then it is necessary to call selection_array.fillna(false) first.

Reporter: Wes McKinney / @wesm
Assignee: Ben Kietzman / @bkietz

PRs and other links:

• GitHub Pull Request #4366

_{Note: This issue was originally created as ARROW-1558. Please see the migration documentation for further details.}

[asfimport]

Neal Richardson / @nealrichardson:
@xhochy have you started work on this already? Or is this available for someone else to pick up?

[asfimport]

Wes McKinney / @wesm:
I don't believe so, Uwe assigned this issue 9 months ago so I'm unassigning

[asfimport]

Wes McKinney / @wesm:
Issue resolved by pull request 4366
#4366